1. Field of the Invention
The present invention is directed to an apparatus for manufacturing lightweight concrete during the installation of roof decks of a building structure.
2. Discussion of the Related Art
Lightweight concrete is used extensively in the construction of buildings, and particularly in the installation of roof decks and related roof systems. When installing a roof deck on a building structure, lightweight concrete is disbursed, in a slurry coat, to form a topping layer of insulation over underlying roofing materials. Lightweight concrete typically consists of a combination of Portland cement, one or more foaming agents, water and possibly other chemical agents. To insure proper distribution of the lightweight concrete, prior to curing, it is important to discharge the lightweight concrete mixture on the roof deck shortly after the mixing process. Presently, the process for manufacturing lightweight concrete for on-site installation involves the use of one or more compressors, a pressurized tank for holding chemicals, a separate cement mixer, a concrete pump and an elaborate series of hoses for directing water, chemicals, cement, foaming agents and other chemicals to be mixed and discharged in rapid action. Using this method, the lightweight concrete is manufactured in batches and then discharged in a slurry coat on the roof deck. After each batch is exhausted, subsequent batches are manufactured and discharged until the installation of the lightweight concrete roof insulation is complete. The presently used method of on-site manufacturing of lightweight concrete presents several problems and concerns. Specifically, pressurized hoses have been known to burst, subjecting workers to potential serious injury. Additionally, the numerous equipment and hoses needed to mix the components of the lightweight concrete mixture often become tangled, which results in possible equipment malfunctions and operational delays. A further problem with the presently used mixing process is the inability to produce uniform and consistent mixtures of lightweight concrete which meet code requirements, such as consistency in pull strengths throughout the roof deck. Because the mixing process, and particularly the rate and amount of flow of each component in the mixture relies on human judgment, it is difficult, if not impossible, to produce uniform and consistent mixtures throughout multiple batches.
Accordingly, there is an urgent need in the construction industry for a contained and portable apparatus which is specifically structured for on-site manufacturing of lightweight concrete in a safe, controlled and highly predictable process to produce a continuous on demand supply of lightweight concrete in a consistent, uniform mixture.